Every survey is inherently biased, because the answers only come from people who were able to be contacted and are willing to answer surveys. It's also going to be biased because many people who use multiple languages will have subjective and incorrect opinions on which language was their primary language.
What it does indicate is general categories and trends. Various other surveys by other parties also show the same trilogy of Java, Javascript, and Python as being the most commonly used languages, so this survey fits in with other independent sources.
Biting the hand that feeds IT
